say it: SIM-puh-thahy-zur
sympathizer is a noun meaning "a person who commiserates with someone who has had misfortune". It carries 2 recorded senses.
a person who commiserates with someone who has had misfortune
someone who shares your feelings or opinions and hopes that you will be successful
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for sympathizer come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.